3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault <g.nault@xxxxxxxxxxxx> commit f664e37dcc525768280cb94321424a09beb1c992 upstream. If 'session' is not NULL and is not a PPP pseudo-wire, then we fail to drop the reference taken by l2tp_session_get(). Fixes: ecd012e45ab5 ("l2tp: filter out non-PPP sessions in pppol2tp_tunnel_ioctl()") Signed-off-by: Guillaume Nault <g.nault@xxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> [bwh: Backported to 3.16: Also call session->deref in both cases] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> --- net/l2tp/l2tp_ppp.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -1231,15 +1231,22 @@ static int pppol2tp_tunnel_ioctl(struct l2tp_session_get(sock_net(sk), tunnel, stats.session_id, true); - if (session && session->pwtype == L2TP_PWTYPE_PPP) { - err = pppol2tp_session_ioctl(session, cmd, - arg); + if (!session) { + err = -EBADR; + break; + } + if (session->pwtype != L2TP_PWTYPE_PPP) { if (session->deref) session->deref(session); l2tp_session_dec_refcount(session); - } else { err = -EBADR; + break; } + + err = pppol2tp_session_ioctl(session, cmd, arg); + if (session->deref) + session->deref(session); + l2tp_session_dec_refcount(session); break; } #ifdef CONFIG_XFRM